Terminal exit for forced air circulating systems



April 22, 1969- 3,439,601

TERMINAL EXIT FOR FORCED AIR cmcubuiue SYSTEMS K. R. COOPER Filed ma 19. 196'! INVENTOR. KENNETH R. COOPER Attorney 7 United States Patent 3,439,601 TERMINAL EXIT FOR FORCED AIR CIRCULATING SYSTEMS Kenneth R. Cooper, Don Mills, Ontario, Canada, assignor to Contemporary Walls Limited Filed May 19, 1967, Ser. No. 639,699 Int. Cl. E04f 17/04 U.S. Cl. 98-90 3 Claims ABSTRACT OF THE DISCLOSURE A terminal exit for forced air circulating systems of buildings incorporating the sill member of a window as the termination of the forced air system, and further incorporating an air chamber within the wall structure beneath the window, and communicating with the sill member and with the air treating and circulating plant.

Field of the invention The invention relates to a wall system incorporating the termination for a forced air circulating system for buildings. More particularly, the invention provides a termination or terminal exit for forced air circulating systems incorporated within a wall structure of a building.

Background of the invention It is the trend to construct large buildings, such as offices, apartments and hotels, having considerable window area. It is also the trend in such buildings to provide for peripheral air exchange systems wherein treated air is forced into an enclosed volume: such enclosed volume may be an entire floor of the building or a portion thereof, or individual oflices. The air return grills by which circulation is established, and from which the air is returned to an air treating plant in the building for cooling and/or heating, are usually located in the ceilings and may be associated with light fixtures, etc. The return portion of an air system for ofiice buildings forms no part of this invention.

Modern day office buildings and others, basically rely for heating and cooling on forced air systems. These are the so-called air conditioned buildings, but more practically they may be referred to as air treated buildings. That is to say, depending upon the requirements in any particular zone within the building, warm air or cooled air or a combination thereof is blown into the enclosed volume defining such a zone and circulates within such volume before returning to the air treating plant. The air treating plant provides heat exchangers both for cooling and heating the air. In many office buildings the air circulation systems from the heating plants comprise separate ducting systems for cooled air and for warmed air. However, the present invention is particularly directed towards the terminal exits for an air circulating system and has no regard as to whether or not such system is for warm air or cooled air, or both; provided only that the flow of air within the system is forced from some pump or fan means.

When peripheral exits are provided for forced air systems, it has been the practice to place the ducts in the cavity between the ceiling and floor and to bring the ducts to an exit vent. The treated air is then blown from the vent into the room or other such enclosed volume as intended. However, most of the previously known vents and ducts have required a wide box construction placed outside the walls and beneath the Windows placed in the walls, and a considerable portion of usable floor space is lost due to the encroachment thereon of these wide structures. For example, in a typical office building having exterior (i.e., window-to-window) dimensions of fifty 3,439,601 Patented Apr. 22, 1969 'ice feet by eighty feet and having air exit structures of one foot width situated entirely about the periphery of each floor, the following analysis is made:

This represents a reduction of slightly greater than 6.4% in the usable floor space per floor. Or, in other words, in a sixteen story building, one additional floor is required to make up for the usable floor space lost in the air exit structures beneath the windows in the outer walls of each floor.

It should be noted that in such an ofiice building as discussed above, and particularly on northerly or easterly exposures in cold weather, there is a very high probability that frost Will form on the inside on the windows when the humidity inside the building is controlled at an acceptable level for occupancy. This is particularly so when the building is single glazed. It has been found that wide terminal exit ventilating systems as discussed above, blowing warm air from vents located up to a foot or so away from the windows, and beyond the window sills, have been unable to prevent icing of the windows; nor have such systems been successful for de-icing Windows once they have been covered. It may, therefore, happen that in such conditions a window, particularly when single glazed, may be upwards of 50% coated with frost or ice.

As a further comment, it should be noted that the icing problem of windows has been at least partially overcome in the past by double glazing windows. This requires two panes of glass fitted into a window frame, and having a dead air space therebetween; or more usually, an hermetically sealed two pane unit.

Especially with single glazed Windows having no air vent immediately beneath them, or even with the wide air vents previously used, and which were away from the window sill, a downdraught may be only an inch or two in thickness, but it is enough to establish a cold air/warm air front within the room; and to establish a draught condition around the periphery of a building but within the enclosed volume for which a heating plant is intended to be operated.

Summary of the invention It is an object of this invention to provide terminal exits for forced air circulating systems for buildings in which the area taken by the peripheral air exits or vent systems is substantially less than has been previously attained.

Another object of this invention is to provide a wall structure for buildings which includes therein the necessary terminal exits for a forced air circulating system.

Yet another object of this invention is to provide peripheral exits for a forced air circulating system in a building, and which permits a greater and more eifective heat barrier at the periphery of the building.

A still further object of this invention is to provide terminal exits for forced air circulating systems in a wall structure for buildings, which provide greater ice-preventing and de-icing of the window surfaces.

Brief description of the drawing These and other objects and advantages of the invention will be more evident in the following discussion in association with the drawing in which;

The figure is a cut-away perspective view taken through a section of a wall structure which incorporates the present invention.

Description of the preferred embodiment The drawing illustrates a typical through-section of a wall, but using a structure incorporating the present invention. However, certain of the features illustrated in the drawing may concern matters of architectural choice or detail, and the following description is not intended in any way to be limited to the precise details of construction illustrated in the drawing. For example, the drawing illustrates a ceiling to floor crawl-space found in an office building having basic steel structure, and which may have an interior height between floor and ceiling of any dimension ranging from several inches to three feet or more. Further, the drawing illustrates a particular exterior construction in-which the entire outer surface of the building is clad with glass. However, the drawing also illustrates the terminal construction for a forced air circulating system which includes an air cavity and sill construction as contemplated by the present invention.

In modern building construction a crawl-space is enclosed within the volume bounded on the bottom by a ceiling 11 and on the top by a floor 12. The ceiling 11 may be any sort of suspended or placed ceiling, and in this case, it is illustrated as being supported by supports 13 at its outer edge. The floor 12 is of concrete which may be cast in place or pre-cast slabs, and which is supported such as by wide flanged I-beams 14. Placed over the floor 12 is a floor covering 15 which may be tile, broadloom, hardwood, or any other floor covering desired. In the particular structure shown, a floor corner-moulding 16 is illustrated being placed between wall panel 17 and floor 12 so as to provide a finished rounded corner construction where the floor covering 15 runs into the wall.

The wall panel 17 may be of such material as plasterboard, and extends from beneath the window sill past the fioor and to the upper side of the lintel on the windowunit of the storey beneath. Spaced away from panel 17 there is a spandrel unit 18. This unit comprises a basic exterior spandrel structure and may be of pre-cast concrete or any other suitable material. It is understood, of course, that the interior wall structures illustrated have no bearing function. In the exterior wall structure for the particular design chosen in this illustration, there is a sheet of glass 19 forming an additional exterior spandrel and which is provided primarily for the sake of appearance. A cavity 20 is enclosed between glass 19 and spandrel unit 18 and may provide a certain insulating value. There is no provision shown in the illustration for additional insulation, but unit 18 may be chosen of laminar or other material having the requisite K factors as determined by the architect.

There are various panels of window glass illustrated at 21, 21a, and 21b. All of these panels of window glass are of the necessary translucent variety and having the requisite tinting and structural specifications as determined by the specific architectural design chosen. Separating the window panels 21 and 21a, is a post 22, and this post 22 may extend the full height of the wall and through the ceiling to floor crawl-space as illustrated at 23.

At the exterior face of the building between the spandrel glass 19 and the window panels 21 or 21b, there is located a facing strip 24, which provides for the necessary finishing and which includes the requisite sealing gaskets such as shown at 25'. On the inside face of the wall, there may be located a wall panel 26. This wall panel provides a more finished appearance to the wall and is held in place by mouldings 27a and 27b. The distance between mouldings 27a and 27b is, in effect, the height from floor to sill 28, and is a matter of architectural design choice. Hence the breakline 29 which illustrates this fact.

Sill 28 is the upper face of a sill member 30. The sill member includes at least one slot 31 in its upper face, and at the bottom it may have downwardly extending lips 32 which fit between interior wall panel 17 and spandrel unit 18. An opening 33 into the hollow interior of sill member is thereby effected between lips 32. Opening 33 may comprise a series of openings or perforations, as determined by the architect and by manufacturing techniques of the members 30. The interior of sill member 30 communicates through the opening 33 at the bottom thereof with a cavity 34 which is defined between interior wall panel 17 and spandrel unit 18. It is not essential that lips 32 be included in sill member 30, provided however that an air-tight communication is effected between cavity 34, through sill member 30 to slots 31, as will be more fully discussed below. Cavity 34 has for its function the operation as a windbox, and communicates through opening 35 with air ducts such as shown by ghost lines at 36.

As treated air (warmed or cooled) comes from the fan or pump unit which services the Zone, it is led to individual wall exit structures, such as that illustrated, through ducts as shown at 36. The air has relatively high velocity when it enters the air cavity 34. However, cavity 34, because of its volume, reduces the pressure of the air and elfects a right-angled turn of the flow of air as illustrated by arrow 37. The air flows upwards through cavity 34, through the sill member 30, and exits at slots 31. Because the dimensions of slot 31 are considerably smaller than the interior of the sill member 30, and are usually narrower and slightly shorter than cross-ways dimension of cavity 34, an increase in velocity of the air is effected. A venturi effect occurs across slot 31, and the air blowing through the slot is thereby forced upwards to travel along the inside surface of the glass 21 or 21a. Also, a quiet, whistle or rumble-free exhaust of the air through slots 31 is achieved.

There is also illustrated in the drawing, a member 38 at the lower end of air cavity 34; the dimensions and purpose of which are substantially the same as of sill member 30. However, the illustration is one of a specific wall structure, and it is not necessary that an air exit member 38 be included at the bottom of air cavity 34 to force air downwards over glass 21b. If desired, the bottom of the air cavity can be blanked 0E, and the operation of the forced air terminal equipment is as discussed above. When member 38 is provided, there is an additional flow of air downwards from ducts 36 as illustrated by arrow 39 in ghosted lines; or it may be that air control is arranged so that air blows either up or down through cavity 34, as required.

The material of post 22, members 24, 27a 27b, 30 and 38 may be, by way of example only, aluminum, Monel, steel, stainless steel, and alloys thereof.

It has been shown in the drawings and the above discussion, that the illustrated wall structure incorporates the present invention and provides the necessary peripheral exits for a forced air circulating system. No additional and expensive wall ducting systems are required; nor is there any need for the vent system to be constructed apart from the wall structure and thereby take otherwise usable floor and wall space. It should be mentioned further, that zone controls may be easily effected by the usual means of installing thermostats in the necessary locations, which thermostats would control the temperature and/or volume of air in the duct system.

It may be seen that the provisions of a wall structure having included therein the peripheral exits for a forced air circulating system, satisfies the requirements for the structure for a wall and the forced air system economically. It is only necessary to install the required wall and spandrel panels and to fit the necessary sill mouldings thereto. Therefore, the only expense which may have to he met would be that of the modification of the sill members. However, it should be mentioned that in most ofiice buildings of modern design, sill members are, in any event, required and most particularly with forced air systems. The only other modification is the provision of a panel such as at 17, to provide the air chamber 34. It can be seen that all of the other components for the provision of the Wall structure according to this invention, are standard structural components which would, in any event, be included in the structure of the building.

Since the air exiting at slot 31 is forced upwards along the interior surface of glass 21 or 21a, this air can overcome any downdraught which may have set up near the window. The downdraught would normally rely for its impetus upon the relative density of cold air and its tendency to fall. The forced air moving upwards would be suflicient to overcome that tendency. Further, because the air blows up the inside surface of the window, it can provide for de-icing or ice-prevention of the interior Window surface. Thus, in cold weather the windows may be kept clear more easily than with other systems. Also in cold weather, the warm air blowing through slot 31 up the interior window surface provides a heat barrier between the outside and the interior of the building. No effect of draughts is felt by the occupants, and closer control over temperatures within an enclosed volume, or zone, in the building may be maintained. It may not, therefore, be necessary to provide drapes or other draught disturbing barriers near the surface of the windows; especially on northerly or easterly exposures which would not otherwise require drapes against the effects of a bright sun. It may still be necessary to provide for drapes on southerly or westerly exposures, but these would not necessarily be of heavy material but can be of a scrim or gauze material as required only to present an opaqueness to direct sunlight.

By utilizing the presence of the sill structures beneath the glazing of the windows as exits for forced air in a building, rather than having additional terminal exit equipment on the inside of the walls; it can be seen that floor space previously lost (as discussed above) can be recovered.

Another benefit which flows from the terminal exit structure of the present invention is as follows. With the previously known terminal exit equipment which is placed on the inside of exterior walls and having large box structures as discussed above, such structures are usually continuous along the length of the exterior wall. Room partitions as required are then built to fit around the box structures at the exterior wall. However, with such construction, it has been known to have sound transmission through the box-like terminal exit structures from room to room. With the terminal exit structure of the present invention, there is no direct communication through the air system from room to room, and consequently the likelihood of sound transmission from room to room is greatly reduced.

As has been previously mentioned, the above discussion has been directed particularly towards the wall structure illustrated in the drawing which incorporates the present invention, and an alternative thereto.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A terminal exit for forced air circulating systems, incorporated in a wall structure of a building and comprising:

a hollow sill member having at least one slot in the upper face thereof, the length of the slot being substantially greater than its width and the width of the slot being less than the width of said sill member, and at least one opening at the bottom of said sill member;

said opening at the bottom of said sill member communicating with an air cavity defined at its inner and outer limits by inner and outer wall panels respectively, and having a length and width to accommodate said opening;

and means providing air communication between said air cavity and air ducts leading thereto.

2. The terminal exit for forced air circulating systems of claim 1 wherein said means for communicating said air cavity to said air ducts provides means for communicating a single air cavity to air ducts used for supplying warmed air and cooled air from an air treating plant.

3. The terminal exit for forced air circulating systems of claim 2, wherein said air cavity communicates at its bottom to a member similar to said sill member to effect a downwards flow of air from said air cavity.

References Cited UNITED STATES PATENTS 971,412 9/1910 Scureman 98-90 3,247,895 4/1966 Phillips 98-31 XR 317,265 5/1885 Wood 98-90 923,149 6/ 1909 Davis 9890 1,334,398 3/1920 Plym et al 98-90 XR 2,977,870 4/1961 Bier-Wirth et al 9840 3,187,662 6/1965 Kreuttner 98-40 XR FOREIGN PATENTS 883,523 7/ 1953 Germany.

FRED C. MATTERN, 111., Primary Examiner.

M. ANTONAKAS, Assistant Examiner.

US. Cl. X.R. -54 

